JPH10232010A - Apparatus utilizing energy of municipal waste and analog to thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dissolve the drawbacks that the substantial efficiency of facilities utilizing the energy of municipal waste, etc., is low, and that investment and operational costs are high. SOLUTION: This apparatus utilizing the energy of municipal waste and analog to thereof is equipped with a device 1 in which the waste discharged from the first discharge outlet S1 is ground by the second flow selected for either the inert substance polluted by an organic substance or a burnable heavy chemical element, with a fluidized bed reaction furnace 2 which receives the ground waste, with a solids-separating cyclone 11 in which the gas discharge from the reaction furnace 2 is fed, and with the first heat exchanger assembly 8 which collects the gas discharged from the cyclone 11. This apparatus includes a recuperator boiler 15 which includes a dust removal hopper discharging solid particles from the second discharge outlet S2, the second heat exchanger assembly 23 arranged in the chamber 22 in which gas is fed, and the gas final treatment device in which the solid substance after the treatment is discharged from at least one of the third discharge outlets (S3', S3"). This equipment is equipped with an independent melting and vitrifying furnace 6 which is connected with each discharge outlet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an energy utilization apparatus for municipal waste and the like.

More specifically, the present invention relates to a process comprising: a first stream of an inert substance whose rejects are substantially contaminated with no organic substances, and an organic substance or a heavy combustible element (heavy element);
a second stream of inert material contaminated with the y elements), wherein the second stream grinds the waste discharged from the first outlet; and a circulating fluidized bed reactor for receiving the milled waste. -A solids separation cyclone to which the gas discharged from the reactor is supplied; and-the gas discharged from the cyclone is discharged, comprising a first heat exchanger assembly and discharging solid particles from a second outlet. A recuperator boiler including a dust hopper to be removed;-a second heat exchanger assembly disposed in a chamber to which the gas is supplied;- The present invention relates to an energy utilization device for municipal waste and similar products including a final treatment device.

[0003]

2. Description of the Related Art Such a reactor is disclosed in Patent Document FR-27.
35041.

[0004] It is also known to vitrify fly ash of municipal waste treatment equipment in order to obtain the dissolution of inorganic substances and the burning of carbon-containing substances.

It is known to install such a melting and vitrification furnace on the main line of the installation. Such a vitrification is disclosed in patent document DE 43 33 510.

In such an installation, a post-combustion chamber for the gas leaving the pyrolysis or gasification system (rotary furnace or fluidized bed reactor) is provided downstream of the reactor and the molten ash exiting the chamber is provided. Is vitrified in the quenching bath.

[0007]

Such a vitrification system requires the supply of a large amount of external energy such as natural gas, oxygen, or electricity due to the large amount of solid matter processed by vitrification. . For example, the calorific value of the solid substance discharged from the reactor is insufficient to secure the melting temperature of a large amount of inert substance.

As a result, the real efficiency of energy production of such equipment is significantly reduced, while the investment and operating costs are very high.

The present invention solves these problems relating to the efficiency of such waste energy utilization facilities.

[0010]

According to the invention, the apparatus comprises, for this purpose, independent melting and vitrification furnaces connected to each of said outlets by a passage control line.

With this arrangement, what is needed to improve the overall economics of the management of solid residues and to optimize on a case-by-case basis according to the specific or regional conditions of collection. Only the material can be melted and vitrified. Also, according to the present invention, the consumption of heat energy from wastes for performing this can be minimized, and high heat efficiency can be maintained.

[0012] It is possible to use a variety of melting and vitrification equipment that is particularly adapted to the quality of the waste to be treated. Thus, wastes or fuels with thermal properties that differ significantly from conventional household waste, or wastes or fuels that are difficult to process with a fluidized bed due to the danger of agglomeration at low density or low temperature, may vary. It is possible to process the substance.

[0013] This arrangement also has the advantage of preventing the equipment from becoming unusable in the event of problems with the melting and vitrification furnace. In fact, since the melting and vitrification furnace is not on the main line of the equipment, the operation of the melting and vitrification furnace can be stopped without stopping the main line.

According to a preferred embodiment, a dust remover is disposed between the recuperator boiler and the second heat exchanger assembly, the solid particles of which are connected to the melting and vitrification furnace by a passage control line. Discharged from the outlet.

Conventionally, a device for filtering fly ash is located downstream of the heat exchanger, and thus removes gas at low temperatures. However, at low temperatures, dioxins are reformed and heavy metals with the highest contaminating capacity are recondensed. The result is contaminated and hardened fly ash.

According to this aspect of the invention, a dust remover is provided between the recuperator boiler and the second heat exchanger assembly.
Preferably a cyclone is provided. The result is fly ash that is extracted at high temperatures and is therefore substantially free of heavy metals and dioxins.

[0017] The final treatment device preferably comprises a filter through which the solids are discharged by a passage control line from an outlet connected to the melting and vitrification furnace.

[0018] It is further advantageous that the final treatment device comprises a smoke cleaning device in which the cleaning cake is discharged from a discharge connected to the melting and vitrification furnace by a passage control line.

In order to bring the sieve residue to be vitrified to the correct particle size, a sieving mill is installed between the first outlet and the melting and vitrification furnace.

[0020] The reactor advantageously has an internal dense bed with a collection chamber for the pyrolysis gases injected into the melting and vitrification furnace.

Advantageously, the melting and vitrification furnace comprises a quenching bath and the washing device comprises a device for treating liquid waste in which waste is injected into the quench bath of the melting and vitrification furnace. .

According to a preferred embodiment, the melting and vitrification furnace comprises a ball-shaped hearth and walls forming a refining barrier associated with the discharge or scooping of the surface layer of the molten mass.

Preferably, the dissolved material is first cooled on a drum which is internally cooled by water and then in a quenching bath.

The melting and vitrification furnace preferably comprises a quenching bath in which the combustion gases generated by the furnace are cooled.

Hereinafter, the present invention will be described in detail with reference to the drawings showing a preferred embodiment of the present invention.

[0026]

DETAILED DESCRIPTION OF THE INVENTION As shown in FIG. 1, an energy utilization system for municipal waste and the like includes a circulating fluidized bed reactor 2 for receiving crushed waste. This reactor is preferably of the type described in patent document FR-2735041. Thus, the reactor comprises a first side dense fluidized bed 2A, which is located on the wall of the reactor containing the grinding waste supply line and where gasification of the grinding waste occurs, and a second side dense fluidized bed comprising a superheater. Floor 2B. A conduit for extracting non-fluidizable heavy components is located at the base of the first side dense fluidized bed 2A, and sorts large particles that cool the heavy components and extract non-fluidizable inert materials. These components are transferred to the apparatus 3, and other substances are recharged into the reactor 2.

On the upstream side of the reactor 2, waste as raw material is pulverized by, for example, a shearing device including one or two rotary shears, and is further pulverized according to the type of waste to be treated. Magnetic and induction separators and / or drums may create inert materials and substances that may create agglomeration hazards (ferrous, non-ferrous, gravel,
The glass is put into the preparation device 1 for discharging the glass.

The crushed waste is put into the reactor 2 and
The sieve residue is sorted into two streams in a sorting device 4, which preferably comprises a weight classifier or a blast classifier.

The first stream of inert material (glass, gravel, iron shavings), which is hardly contaminated with organic substances, is large particles (co
arse-particles) into a sorting device 3 where they are mixed with the hot substance exiting the reactor 2,
It is used for cooling the non-fluidizable inert substance discharged from the reactor 2 and is subjected to a heat treatment at about 400 to 500 ° C., which can be called thermal cleaning and removes organic substances.

Thus, under the apparatus 3 for sorting large particles, solid residues consisting of inert and / or large substances (stone, glass, ceramic, iron shavings) from which organic substances have been removed and which are hardly oxidized. Stream 8 is obtained, which facilitates the recycling of the solid residue.

The second stream, consisting of organic substances or inert substances contaminated with heavy combustibles, has a carbon content of 5%.
, And cannot be directly reused, and is discharged from the first discharge port S1. From this discharge port, the sieving and pulverizing device 5 installed on the passage control line to the melting and vitrification furnace 6 is used. It is thrown.

The first internal dense fluidized bed 2A is connected to a melting and vitrification furnace 6 through a pipe 7 separated from a main stream of combustion gas.
A sampling chamber for the pyrolysis gas 2A 'injected into the inside is provided.

The reactor 2 also comprises a fines separator 9 which can separate ash at the lower part of the reactor 2 and recirculate solid particles whose size is compatible with fluidization into the reactor. This device 9 is also used for re-injecting the fine particles output from the sieving and crushing machine 5. These fines still contain an organic part which can be used for the combustion of the fluidizable inert substance, the inclusion of which reduces the consumption of the basic sand in the reactor 2. As these fine sieve residues move through the fine particle sorting apparatus, thermal cleaning of components that cannot be fluidized is also performed. The available clinker 10 is discharged from the particle sorting device 9.

Therefore, the quality of the sieving residue is improved by moving the sieving residue via the large-sized particle sorting device 3 and the fine-particle sorting device 9 connected to the reactor 2. This avoids the need to store the sieving residue at a second-level public landfill.

Downstream of the reactor 2, the smoke comprises:-a cyclone 5 for separating solids; and-gas leaving the cyclone 11 is discharged and passes through the first heat exchanger assembly 18, more precisely the evaporator. A recuperator boiler 15 comprising a boiler including a dust removal hopper 15A from which solid particles are discharged from a second discharge port S2; and-hot dedusting of smoke from which solid particles are discharged from a discharge port S2 '. A second cyclone 16; a second heat exchanger assembly 23, more precisely an economizer, arranged in the chamber 22 to which the gas is supplied;
The gas discharged from 3 'and S3 "passes through a final treatment device.

More specifically, the final treatment device is provided with a filter 17, preferably a sleeve filter, which is provided with an activated carbon injection device and discharges solid particles from the discharge port S3 ', and a cleaning filter from which the cleaning cake is discharged from the discharge port S3 ". The purified smoke is exhausted from the flue 30, including the device 19.

The cleaning device 19 is a liquid waste processing device 21.
Is provided.

The outlets S1 to S3 "described above are all connected by a passage control line to a melting and vitrification furnace 6 independent of the main lines of the equipment already described.

In this device 6, the pyrolysis gas captured from the fluidized bed 2A and, in some cases, the residue of the sieve (contaminated solids) are discharged from a solids recycling device containing a large amount of thermal energy. With some plastic waste 20, melting energy is supplied. The auxiliary material in the melting furnace 6 is air or oxygen-rich air, depending on the desired temperature. In the latter case, the oxygen-enriched air is supplied by the diaphragm device 21, and when the oxygen is depleted, it is used for fluidizing the sorting devices 3, 9 and the fluidized bed reactor 2.

The discharge port S2 of the recuperator boiler 15
Depending on the size of the fly ash coming out of the outlet S2 'of the cyclone 16, the outlet S3' of the filter 17, and the size of the cake coming out of the outlet S3 "of the washing device 19, these substances can be melted and vitrified. Conversely, the particle size of the retentate of the sieves of the sorting device 4 for preparing the waste is very variable and in some cases can be large, so that the outlet S1 and the dissolving and A sifting and crushing machine 5 is required between the crushing machine 6 and the vitrification furnace 6.

The melting and vitrification furnace 6 can be designed differently depending on the amount of material to be treated and the degree of melting desired.

The melting and vitrification furnace separates the two parts to be vitrified: a large part, which generally results from low sieving residues with a low heavy metal concentration, and a more contaminated powder part, which results from the extraction of fly ash. The furnace type described in Patent Document FR-2716524, which can be controlled and melted separately, can be used.

FIG. 2 is a view showing another embodiment of the melting and vitrification furnace.

[0044] The hearth 60A of the furnace is provided with a ball (bo
wl). The pyrolysis gas is injected from the pipe 70, and the fly ash is dissolved by the temperature. The furnace also comprises a burner 61 to which air or enriched air is supplied. The septum 60C forms a purification barrier connected to the outlet or scoop 60D of the surface layer of the dissolved substance mass. The molten salt is discharged in this way. In addition, in order to improve the quality of the melting bath, a metal drain device 60E that has fallen to the bottom of the hearth is provided.

The device may optionally include a barrier partition 60.
Downstream of C may include an emergency oxygen burner 61 ', the melt flows from the tap of the furnace onto a drum 62A which is internally cooled by water. The drum 62A can prevent sudden water soaking (water quenching) in the bath 62 and excessively rapid solidification that is detrimental to the physical properties of the vitrified material.
Vitrification continues in the quenching bath 62 on the cooling plate conveyor 62C before the vitrified material 64 is discharged from the screw conveyor 62D through the water seal that ensures the airtightness of the smoke to the outside.

This embodiment achieves a crystallization level that guarantees very long-term stability and can effectively improve the quality of the vitrified material.

The gas generated in the melting furnace 6 is immersed and cooled by blowing air into the vitrification bath. This rapid cooling prevents the re-formation of dioxins which are particularly contained in the mixture of fly ash and activated carbon coming out of the filter 17. This rapid cooling also captures the secondary ash flying above the melting bath and most of the heavy metals that evaporate during melting, thereby preventing them from being sent back into the main smoke treatment unit. .

Next, the smoke is exhausted from the pipe 71 and sent into the cleaning device 19.

In order to correct the evaporation, melting and replenishment of the water in the quenching bath of the vitrification furnace 6 is performed from the drainage part of the treatment of the liquid waste 21, whereby the pH can be adjusted and heavy metals can be removed. Solubilization can be improved.

The cooling circuit 24 advantageously expels the calories of the vitrification bath and utilizes it for reheating the feed water.

[Brief description of the drawings]

FIG. 1 is an overall view of a municipal waste energy utilization apparatus according to the present invention.

FIG. 2 is a cross-sectional view of an embodiment of a melting and vitrification furnace.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Apparatus which grinds waste 2 Fluidized bed reactor 2A 1st side dense fluidized bed 2A 'Pyrolysis gas 2B 2nd side dense fluidized bed 3 Apparatus which sorts large-sized particles 4 Sorting apparatus 5 Screening and crushing apparatus 6 Melting and glass Furnace 7 Pipe line separated from main stream of combustion gas 8 Solid residue flow 9 Particle sorting device 10 Clinker 11 Cyclone 15 Recuperator boiler 16 Second cyclone 17 Filter 18 First heat exchanger assembly 19 Cleaning device 20 Plastic waste Object 21 Apparatus for treating liquid sewage 22 Chamber to which gas is supplied 23 Second heat exchanger assembly 24 Cooling circuit 30 Flue 60A Furnace floor 60B Port 60C Partition wall 60D Discharge or scoop port 60E Drain device 61 Burner 61 'Emergency oxygen Burner 62 Quenching bath 62A Internally cooled by water Drum 62C Cooling plate conveyor 62D Screw conveyor 64 Vitrified material 70, 71 Pipeline S1-S3 "

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F23J 15/02 F23J 15/00 C

Claims (10)

[Claims] 1. The screen residue is separated into a first stream of an inert substance substantially contaminated with organic substances and a second stream of an inert substance contaminated with organic substances or heavy combustible components. A device (1) for crushing the waste discharged from the first outlet (S1) by two streams, a circulating fluidized bed reactor (2) for receiving the crushed waste, and gas discharged from the reactor (2) A solids separation cyclone (11) to which the gas is supplied, a gas discharged from the cyclone (11) is released, and a first heat exchanger assembly (18) is provided.
A recuperator boiler (15) including a dust removing hopper from which solid particles are discharged from 2), a second heat exchanger assembly (23) disposed in a chamber (22) supplied with gas, At least one third outlet (S
3 ′, S3 ″), and an independent melting and vitrification furnace (6) connected to each of the outlets by a passage control line. Energy utilization equipment for municipal waste and similar products. 2. A dust removing device (16) is provided between the recuperator boiler (15) and the second heat exchanger assembly (23), and the solid substance is melted and vitrified by a passage control line. 2. The device according to claim 1, wherein the gas is discharged from a discharge port (S2 ') connected to the furnace. 3. The final treatment device comprises a filter (17) through which solid substances are discharged by a passage control line from an outlet (S3 ′) connected to the melting and vitrification furnace (6). The apparatus according to claim 1 or 2, wherein 4. A smoke-cleaning device (19,2) wherein the washing cake is discharged from an outlet (S3 ″) connected to a melting and vitrification furnace (6) by a passage control line.
Apparatus according to any one of claims 1 to 3, characterized in that it comprises (1). 5. The method according to claim 1, wherein a sieving and pulverizing device is provided between the first discharge port (S1) and the melting and vitrification furnace (6). apparatus. 6. The reactor according to claim 1, wherein the reactor has an internal dense bed provided with a chamber for collecting pyrolysis gas injected into the melting and vitrification furnace. An apparatus according to claim 1. 7. The melting and vitrification furnace (6) comprises a quenching bath, and the washing device treats liquid waste in which the waste is injected into the quenching bath of the melting and vitrification furnace (6). 21.
Or the apparatus according to 4. 8. A septum (60C) forming a refining barrier in which a melting and vitrification furnace (6) is combined with a ball-shaped hearth (60A) and a discharge or scooping opening (60D) for the surface layer of the molten mass. Apparatus according to any of the preceding claims, comprising: 9. The method according to claim 8, wherein the dissolved substance is first cooled on a drum internally cooled by water and then cooled in a quenching bath. Equipment. 10. Apparatus according to claim 1, wherein the melting and vitrification furnace comprises a quenching bath in which combustion gases generated by the furnace are cooled. .